Centrifugal cut-out.



`LEvI wunoR'iiNG; '0E IANcestrEi.,l PENNSYLVANIA, Assicrivoit oFONE-THIRD To CHARLES E. STAUEEER'AND ONE-Tmnnroyia. GEANT STAUEEER, orLANCASTER,

rEivNsYvANia.

To all whom t may concern i Beit known that-I, LEvI W.

State of Pennsylvania, have invented cer tain new; and usefulImprovements inCenf trifugal Cut-Outs;l and I do hereby declare ment andwherein the auxiliary starting coil description of theinvention,y suchas 6Will enable others skilled in the art to which it 4 appertain's tomakeand .use the. same., v

1` `This invention relates to centrifugal cutscribed in connection withthe accompanyouts particularly designed foruse on that class of singlephase alternating-current rotors which arewstarted rloyphase displace orwinding must be cut out after starting. The cutout'of the presentinvention may also be utilized to advantage elsewhere for automaticallyopening an electric circuit when a predetermined speed of a rotor isAThe most common cutout of thiskind utilizesthe centrifugal forcedeveloped by the revolving member for opening thecircuit. As ordinarilyapplied, Contact members or. brushesa-re yieldingly mounted. on therevolving member or rotor and 'are held by springs in sliding contactwith sta'-`r` tionary collector rings whichare inthe electrical circuitof the starting winding. After I the revolving member reaches a certainspeed the centrifugal force overcomes the r force of the-.springs andthe brushes are thrown vout away from the collector rings, thus openingor breaking thestarting cir cuit. ber. slows down to a speed where'thecen- 'trifugaly foi'ce exerted on the brushes is the frictional wearoveran extended surface less 'than that exertedsby the springs, thebrushes move into engagementwith-ythecollector rings again, and thestar-ting circuit is closed.

lA cutout constructed as justdescribed is subject to 'considerable wearfrom arcingl and also from friction of the brushes against the collectorrings.

. It is the'obj`ect1-of'this invention tov sub-v stantiallyreduce' thearcing and frictional wear,and to this end to accelerate .the movementof the brushes away from the collector rings when lthecut out occurs, todistribute of the brushesfto provide a tensionvfor 'the y4I-Ioizri'ile., a citizen o-f theUnited States, residing at. Lancaster,inthe'county of Lancaster andI Inversely, qwhen the revolving inem-4 CE'NcrniFucini'1 oUT-oU'r.

` spcification of ittersratent.r Patented Apr, 13,1915. f Appiictmninedkinury 1o, 19.13. seriai No. 741,290. l i

brushes :which is yindependent of the ten lsion acting against thecentrifugal force,

and tor makethe cut out point on the brushes different from the startingpoint thereon,

'that is to say'I the point on the brushes which engages the collectorrrings when' the cut out, takes placev different from the point on said'brushes which is in. contact with .said

rings 'at the start, thus protecting the con-l `tact at the start fromany blistering'that may occurwhen'the circuit is broken.

y The invention willbe first hereinafter deing drawings, which.constitute apart of this specification, andy then defined with.

-parts throughout; Figure 1 `is a side view fofv the frotor of an`induction motor t0 which a .cutout embodying this invention is applied,only -a fragment of the inotor'casing for y supporting rthe collectorringsv ybeing elevationl with the brushes. in-the position shown; Fig.-2 i's a section taken on the line .i2-2 of Fig. l, .showing the yrotorin end 30 they occupy yat the start; Figs. 3 'and-4 are.A y

similar views, illustrating4 the respective positions of the brushesjustbefore andvafter k'Referring'to Figs.y 1 ltoil: inclusive yof theYdrawings, A .designates the laminated body ofthe rotor and a its shaft.To one end of; said body, and insulated froinfi'tfthere is secured akbracket B having al postj lon.

of said lever. the `brushes c and .c1V are pivot.-

ed vbymeans of a pin or rivet c2. The twobrushes are separated; fromther body of the lever by bosses c3 and c4 around which are `mountedhelical springs'c5 and c6 which by l acting between thelever andthebrushes which is lpivoted a lever C. On the -fryend respectively',extending at the opposite side ofI the pivot pin from their lieadsorfric# .tion ends and balancingthe ,latter ends.

The bracketv B also .has other. posts or projections b1 and b2 which actas stops to limit the movement of theleverC rand the tailsl of thebrushes as .will he hereinafter. eX- plained. Still another post orprojection b3 stop b2. The` springs cfand c?, fhoweverV keep the heads'of -tliebrushes in Contact" with theV collectorV rings "independent ofthe i tension 4of the spring Zr* at al minimum pres' sure untilthe'tails osaidbiushescome in.

is mounted on the bracket, this one being A fragmentof the motor casingstator,4 is indicated at D andisprovided'with a collar or sleeve claround Kthe shaft @of the rotor. l l mounted on this sleeve orcollarandare 1nsulated from each other andfioni the'casf ing. .The brushes areheld incontact with 4the respective collector rings by the springs 1 'c5and c when the rotor. is at rest and until` -it reaches thepredetermined speed at which the cut o ut is'desi'gned to occur.

In operation, asthe rotorgathers momen'- IV lclaim Aas new and vdesirevto secure by Lety :ters-Patent of.- the lUnited Statesl is':

' l. A centrifugal .starting switch for elec# tum after starting,centrifugal 'force throws the lever C' outward -,against the tension ofthe spring .54,504 that said lever moves away from the stop blfa-ndinltherdirection of the contactwith the stop b2. vFurther outwardmovement. of the lever under .the influence` of the increasingcentrfugalforce will then cause the-heads of the brushesto be quickly moved outaway fromsaid rings byv reason vof the. fact-that thte distance fromthepivotl pin c2 to the fulcruin's of the tails against'the stop b2 isvery much'shorter than theV distance lfrom said pivot 'pin to thecontact points oi the heads of the brushesl upon the rings.4 It willthus `be seen that the cut out doesnot take place untillthepredetermined speed' of thero'tor' is reached, and when ,it

l does-occur, the movement'of the brushes away from the collector ringsis accelerated l to such an extent, as vcom-pared".wt h previous4devices of this kind, that'arcing is greatly reduced. I

During the outward movement of the vlever the point of contact ofthebrushes iupon 'the collector rings shiftslfrom'that'shown in Figi?, tothat shown `in Fig. 3 where the cut out i's'j'ust about to beetfected.Consequently, the frictionalwear on the brushes willbe distributed alongthis extended vcontact spaceinstead of being concentrat'edfat one pointas in previous constructions. vNot onlyis -theA frictional wearverywmuch re.

, duced'bythis improvedk device, buit-it has the further advantage ofmaking. the cut out jcontact point of the'brushesfuponthe col-.lector-.rings diiferent and well removed from :the starting contactvpoint of said `brushes,-

whaereby the 4'contactat"the start is .protected from' anyblisteringthat mayoccur when thecircuitis broken.. The cut out -'point'is placed at the-extremity ofthe contact space` '3 of the brushes whichis 'farthest lremoved' The collector-ringsd1 and d2 are` contacts; are"separated.

vfrom the pivot pin 027,' thus lengthening the i i head end or lever armof the brushes as com- .taneously, At the same time', the tails of the.I

brushes balance 1 the heads thereof,"so"that the only tension on `saidbrushesis that'oi" the springs c? and c-whichact independ- .t

ently ofthe spring b4 that opposes the centrifugal force.' A

tion is not limited to the `details of'construc'- tion hereinillustrated and described, but is only restricted to theessentialstructural'. features and combinations' of parts specied l .in-theappendedclaims -v Having thus .described my inventionwhat` g tric'motors including combination a lfixed contact, a movable contact mounted-on a pared with the tail end or lever arm thereof, y Y

t should bel understoodthat this invenmovable pivotarra-ngedintermediate ofthe.

" endsl of said movablecontact, `resilient* means for normallykeepingthejmovable contactv in lengagement,withthev fixed. `Contactlwhile the pivotfis finovedoutwardyto af certain point bycentri-fugajlforce, and astop adapt-'.

ed tofengage'thetail end of the movable contact when'saidcertan. point'is reached the outward movement of pivot, said stop servmgas a' fulcrumfoi removingthe head end ofsaid 'movable contact from'th 1.00v

fixed, contact fas the pivot of said movable Contact is thrownVfarther'out by yincreasing s centrifugal forcelj 2,l centrifugalstarting'switch for: electric motors including in combination a fixedjcontact, a movable Contact *mounted 'on' a movable pivot arrangedintermediate ofthe 4 endsof said movable contact, resilient means l lfornormally keeping themovable contact vin i engagement with vthejixed.'contact whilethe pivot is .moved ,outward .tofa certain point bycentrifugal force, and fa` stop` adapted Ato f y engage thetail endofth'movable lcontact -Awhen said.' certain pointis .reached in theoutward movementfojf said pivot, v'said-. stop serving" as a fulcri'lmfor Aremoving .the hea'd end of said movable contactgfrom the fixedContact as -thepivot of said movable contact is throfwnf'farther out. byincreasing centrifugalv fforce,` the lstop .engaging z pointv .on the. f4tailjend'jof 'said: 1movab1e contact being .muchnearer the.pivotthereof than-the pointon 1 I theftail end, off .said 'movableContact 'which engagesfthe'f4 fixedV cont 'ct'fjust beforefsaidingfsw-itch, `of a stationary.andI agrotatable said arm,vresilient;meansltendingft i5 starting switch, of av stationary landarotazo l said arm againstl 'the inner stop,;a movablel `A'contactqpivoted intermediate of itsends, onf.; the free end of'saidari'nfand resilient means for holdingthe head lpend of said'movablei.for holding theheadend of'said .movablej contact in engagement withthejxedfcontact said-3ii-m against the. inner'fstop, a movable contnctpivoted intermediate ofitsends onA the 'free end of said arm,andresilient means.

while the pivot .of the movable contact is' moved outward. byntrifugal`force,against' the influence-of said resilient means acting on y 'toincreasing centrifugal force will cause, the

.head end of the movablecontact to be relector z.rings insulated from,each other, a.. frotorfan; "ag-rm .pivoted thereon, stops at either,side `of 1 themfree'end of said arm, rezsilient means v'teriding?Y tohold said'` arm moved from the ixeflcontact. f et. TheA combination Ain4a centrifugal table .member, al Acontact'on said` stationary member,.anarmpivoted on saidrotatablef.` member, stops ateither. sideof thefreeend of said arm, resilientmeans .tending to lhold contactiinengagement with the xed Contact .while the pivot f ofthe movable contact'is moved outward `by centrifugal.forca-.against the influence ofysaidresilient ,means acting on'th'e arm, vuntil .the tail end of saidmovable contact engages-the outer stop, -where`-; vupon further outwardAmovement of.`sa1d y pivot due toincreasing centrifugalA force;-

` will cause the head end offthe movablec'on# tact to be removed fromthe xed Contact, the point on the'tail end of said movable ,contactvengaged by saidy outer .stop being.

much nearer the .movablepivot than the point of the vhead vendwhichengages the"l fixed contact .just before 'said vcontacts'arevseparated.: w

'5.The combination with stationary col`l Vlector rings insulated fromeachother, a rotor, brushes carried thereby and mounted .L o namovablepivot ,arranged intermediatev` of their ends, resilient means forholding the `head .ends of ysaid brushes in engagement withthefrespectivecollector rings while ther f pivotis moved outward to acertainpoint by centrifugal force', and ay stop adapted to engage. thetail endsfof the brushes when said certain vpoint'. is reached in, theoutward movement of saidpivot, said stop servingas afulcrum-ufor.removingfthe headv ends of the brushes from the collectorrings, as the pivot of said brushes is thrown farther out by in--creasing centrifugal force.

6. The combination withstationary col.-

lector rings insulated from each other, av

rotor, brushes ,carried thereby and mounted on a movable pivot arrangedintermedlate of their ends, resilient means for holding the head ends ofsaid brushes in engagement with the respective collector rings while thepivot is moved outward to a certain point by centrifugal force, and astop on the rotor on the tail ends of said brushes engaged by adapted"to `engage the tail ends of` y the.,l brushesmwhen said certain pointis'reached in the outward movement of said "pivot, said stop servingasf'afulcrum forffrenovingjthe head ends 0f thebrushes from. the:collector-.

rings as the pivot of brushes is thrown" farther lout by increasingcentrifugal force,

Vthe points on the tail ends of the brushes e ngaged bythe stopbein'gmuch nearerfthe n movable 'pivots' than the pointson theiheadA `ends ofsaid brusheswhich engage the'col- "lector ringsjust before 4.the cutoutoccurs; ,`1

.. 7. The "combination ,with Lstationar'y A col'-v l vagainst the'inner.stop,`brushes pivoted'interwithf'therespectivecollector ringswhile"th 'e pivots of' said ybrushes are moved outward .bycentrifugalforce, against the inliuence -0f"sa1d resilient meansactingon thearm,

until'Lthe'tail ends of the brushes engage the,y

ateistop, whereupon further: 'outward 'movement of saidV pivotsdueto`increasing centrifugal force will lcause the head.l ends ofithe.brushes to separate from the col-y 'lector ringsl 1- 18, Theicombination ywith stationary [collv lector rings insulated from eachother, a

rotor, yan ar'm .pi-voted thereon, stops at either v.side of the 'freerend of said arm, resilient means tendingfto hold said armagainst rtheInner stop, brushes pivotedintermediate of resilient means for holdingthe `head ends of said rbrushes in engagement with the respectivecollectorrings While the pivots 0f Said brushes aremoved outward'bycentrifugal frce,ag ainst the influence of said resilient means actingon the arm, Iuntil theftail ends of the brushes engage'theouter stop,whereupon 'y further outward movement of said pivots'due to `increasingcentrifugal force will cause the head ends of the brushes to separatefrom the collector rings, the points the outer'fstop being much nearerthe movable pivots than the points on the head. ends of said brusheswhich engage the collector rings just before the cut out occurs.

9. In' 4a centrifugal starting` switch a brush between its pivotal pointandv they pivot rof lthe leur and throw the contact their ends to thefree. end of said arm,.and y f swinging lever carrying a. brush at'itsfree vfpoint ofthe brush out of 'engagenient'with said fixed contact asthe lever is thrown by Veentxjfuigtil force tOW'ard'Said-stOp. 10. In acentrifugal tarting swthi a,

`swinging lever carrying brushesI at its free vend `which are piyotedthereto.; intermediate 'their ends, resillentmens tendnglto throw thelevel-'in an opposite direction tothe` ac .tion of centrifuga1t force"exerted thereon",y `other resilient means tending to,.l 1-o1d"thezv'Contact 'points of the brushes ln engagement `with fixed contacts,asto'p Iarranged nearthe plYotail point' of :the-'brush adapted l'to:enf 5 vgage fsavid'brushes between .the'pivotalpoints' thereofa-nd thepivot of the lever 'and throw the Contactl points of thebrushes'ou't ofen` gagement With said fixed contacts as the

